I did the 11.11.11 old ale and it's currently aging. I also washed the Wyeast 9097 yeast in the primary and harvested it. I'm sure there's probably SOME low quantity of brett yeast left in there but it's going to be minor in comparison to the Saccharomyces. I'm thinking about using the harvested yeast for a stout. This yeast produces interesting flavors in the old ale that I'm curious to see in action on a stout. Plus it's just a freak in the fermenter. After the stout ferments out I'm going to harvest the yeast again. I think that it's unlikely that too much of the brett will be left after the second harvest. I want to make a starter of brett clausenii to mix with the old ale Saccharomyces to make a cool interesting yeast for next year's old ale attempt. My question is, how do you think they will mix? Well? Negatively?

Its my impression and understanding that the brett to Sacch ratio is of little concern with the 9097 Old Ale blend. The Sacch component of the mixed ferment is so fast compared to brett leading to the slow secondary fermentation by brett. I'm sure you know this but I'm just restating.

If anything the washed yeast, depending on when you removed it from the fermentor, will have a decent population of brett if not more brett that the original ratio at pitch. If you have access to a microscope you can often times tell because brett is much smaller. The packaged yeast is not just a mixed fermentation by wyeast it is probably just a yeast cocktail from two separate pure culture fermentations. Then they checked cell counts via a hemocytometer and mixed each package of yeast according to the desired Brett : Sacch ratio.

So my bet it that if you want to use it in a stout you'd be fine just growing it up in a starter and pitching. The brett will always be out numbered by the extremely fast growth rate of sacch in the beginning of fermentation. However, if you want a funkier presence in your stout pitching the extra vial or a grown up starter of brett will certainly get you there.

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What smokinghole said. You are ALWAYS going to get brett, which means extended aging. Could be really great, but if you want a quick turn around and a clean yeast you should just buy another vial of something else.

I was thinking about just using the Sacch. fermentation to ferment out the stout and forgo the bulk aging. Basically get the conversion I want without letting the brett character develop. I know the characteristics of the Sacch. yeast as being a beast in the fermentation department (had massive blow-off). So I'll let it do it's work and then wash it again.